Conditioning the surface of metal in a semi-finished state before additional processing is a necessary and common procedure to preserve the integrity of finished metal products. If not cured, surface defects present in the metal in its semi-finished state can cause severe defects in the processed metal, as well as fouling the processing equipment. Several different surface conditioning techniques are used to cure surface defects present in steel and other metals after processing. Examples of these techniques include grinding, hand chipping, and scarfing.
The most common method of removing surface defects from steel slabs, billets, and blooms is scarfing. Scarfing steel slabs is a process of applying oxygen and gas, usually by a torch, to the surface of the steel slab to oxidize and melt the surface steel. The oxidized material and molten steel, including and adjacent the surface defect, is then blown away from the slab.
Many different methods of manual and machine scarfing are provided in the prior art, each with varying degrees of efficiency. One common requirement of each method is easy access to each surface of the metal to be scarfed. Thus, a metal slab with one surface resting on a platform or rail cart must eventually be turned over or rotated during the scarfing process to expose such surface to the scarfing equipment.
Rotating and handling metal slabs weighing up to 40 tons presents serious practical and safety concerns. One method and system for conditioning metal slabs disclosed in the prior art provides two independently rotatable leaves for rotating a slab in a stationary carrier in a scarfing station. This method and system, however, only provide scarfing access to the bottom and top surfaces of the slab and neglect the outside edges of the slab. This system also fails to provide, inter alia, a movable cart thereby requiring the scarfing equipment to move relative to the rotatable leaves. While other machines are provided in the prior art for handling various heavy objects, none are adapted for use with steel slabs or provide the increased efficiency and safety of the present invention.